Lonazepam, an anticonvulsant and anti-epileptic is a benzodiazepine derivative. It is used to control seizures or fits due to epilepsy, involuntary muscle spasms, panic disorder. It exhibits pharmacological properties which include anticonvulsive, sedative, muscle relaxing and anxiolytic effects. It works by increasing levels of a calming chemical, gamma-amino-butyric-acid (GABA), in the brain. Depending on the patient’s health condition, this can relieve anxiety, stop seizures and fits or relax tense muscles.

Electroencephalographic investigations have shown that clonazepam suppresses the spike and wave discharges in absence seizures (petit mal), slow spike wave, generalised spike waves, spikes with temporal or other locations as well as irregular spikes and waves.

FAST FACTS

• Clonazepam works by increasing levels of a calming chemical in the brain. This can relieve anxiety, stop seizures and fits or relax tense muscles
• The most common side effect is feeling sleepy (drowsy) during the daytime
• Clonazepam is not likely to be addictive if taken for a short time (two to four weeks)
• If patients take clonazepam for more than two to four weeks, the dose will need to be tapered before stopping it
• Titration/ tapering has been made simpler, with the 0.5mg and 2mg tablets now being cross scored*
• Patients must not drink alcohol while taking clonazepam.

Peak plasma concentrations are reached, in most cases, within one-four hours after an oral dose. Bioavailability is 90% after oral administration. At a daily dose of 6mg, divided into three doses, steady-state plasma concentrations are 25-75ng/ml. Steady-state plasma concentrations following repeat doses may be four times (following once daily dosing) to eight times (following three doses/day) higher than those observed after a single dose.

Clonazepam is indicated for:

Epileptic disease: All clinical forms of epileptic disease in children or adults, especially typical or atypical petit mal, focal seizures with elementary or complex symptomatology, generalised primary or secondary tonic-clonic seizures, status epilepticus in all its clinical forms.

Panic disorder: It is indicated for the treatment of panic disorder, with or without agoraphobia.

*Tablet scoring refers to the breakage of a tablet to attain a desired efficacy dose and is an emerging concept in the pharmaceutical industry. The primary reason for the tablet scoring practice is to adjust the dose: dose tapering or dose titrating.